it is an important space in the united states capitol. they remember those great centers of the 19th century. -- centers of the 19th century. -- senators of the 19th century. >> with the north and south wings done in 1819, work finally began in earnest to build the center part of the capitol. the rotunda, huge. >> the original idea that the center space for the united states capitol, the great ceremonial space would be a circular room, a rotunda capped with a dome. >> when this was being built, h was the big thing in town. >> -- it was the big fan in town. -- big thing in town. >> the founding fathers were very familiar with ancient rome. probably some more familiar with roman than their own states, jefferson in particular but washington and others. -- with room then their own states. jefferson a particular but washington and others. -- a jefferson in particular, but washington and others. as construction of the lower 48 feet of the rotunda near completion in the 18 twenties, -- in the 1820's, congress look back at how would be presented